ios - How do I retrieve additional properties for entity matching "max:" expression -


i have fetchrequest returns max value correctly particular key path. set looks this:

nsexpression *keyexpression = [nsexpression expressionforkeypath:@"distance"]; nsexpression *functionexpression = [nsexpression expressionforfunction:@"max:" arguments:@[keyexpression]]; nsexpressiondescription *expressiondescription = [[nsexpressiondescription alloc] init]; [expressiondescription setname:keypath]; [expressiondescription setexpression:functionexpression]; [expressiondescription setexpressionresulttype:nsinteger32attributetype];

the problem need return value property on object matching above nsexpressiondescription. in other words, want value of timestamp property returned managedobject max: value being returned. if set fetch request this: 

    nsfetchrequest* request = [nsfetchrequest fetchrequestwithentityname:@"record"];     request.resulttype = nsdictionaryresulttype;     request.propertiestofetch = @[expressiondescription, @"timestamp"];     request.propertiestogroupby = @[@"timestamp"];

it returns dictionary each of records has timestamp instead of 1 dictionary record matching max value. idea how can result i'm after?

construct fetch request return items want (this dictionary or managed object). rather using max expression though set fetchlimit 1 , add sort descriptor result maximum value distance returned (because first item in result set).


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